(Spoilers ALL) A certain mysterious person

A thought crossed my mind regarding Coldhands. This could be completely wrong and disproved with one good reference, but I can't think of anything that solidly says this is wrong. So here goes...

Coldhands is Benjen Stark's corpse, controlled by Bloodraven

We know Coldhands is some kind of being that exists north of the wall, and he is almost certainly undead. His hands and feet are black from congealed blood, but he still moves about. One thought is that he is Benjen Stark, but a quote from the Children of the Forest makes that sound unlikely. The quote says that Coldhands has been dead for a long time.

My theory is that Coldhands is Benjen Stark, but merely the shell of him. Benjen died north of the wall on his last ranging and came back as a wight, and that Bloodraven warged into the body and is using it as a tool to locate Bran and bring Bran to the cave. We know Bloodraven is a powerful warg, and if the Children of the Forest view Coldhands as Bloodraven, that would explain their thought that he is long dead. They don't even acknowledge the body as anything more than a mask and are referring to the being controlling the body.